The RCMP says Prime Minister Stephen Harper’s former chief of staff, Nigel Wright, is no longer under investigation and won’t face criminal charges for writing a $90,000 cheque to suspended Sen. Mike Duffy.

Wright resigned from his position last year after the payment came to light. He wrote the cheque to Duffy so that the embattled senator could repay his disallowed housing expenses.

When the Mounties began investigating the Wright-Duffy deal last summer, “there were sufficient grounds to pursue the matter with regards to the offences of breach of trust, bribery, frauds on the government, as well as receiving prohibited compensation contrary to the Parliament of Canada Act,” the RCMP said in a statement Tuesday.  

“Upon completion of the investigation, we have concluded that the evidence gathered does not support criminal charges against Mr. Wright.”

In a statement distributed by his lawyer, Wright said Tuesday that his only intention was “to secure the repayment of taxpayer funds.”

“I believed that my actions were always in the public interest and lawful," Wright said.

"The outcome of the RCMP's detailed and thorough investigation has now upheld my position."

The Prime Minister’s Office said Tuesday it’s “pleased” that the Mounties have “made progress in their work.”

“The PMO will continue offering every possible assistance to the RCMP’s investigation,” it said.

When news of the $90,000 cheque broke in the midst of the Senate spending scandal, Harper initially said he accepted Wright’s resignation “with regret.”

But his tone later changed, and he told the House of Commons on several occasions that Wright had acted alone and must be held responsible for his actions.

The matter is now back in the hands of Conflict of Interest and Ethics Commissioner Mary Dawson.

Her office said Tuesday that RCMP investigators have told her they are no longer investigating Wright and that no criminal charges will be laid against him.

“She is reviewing the matter and will not comment further at this time,” her office said.

Duffy still under investigation

Duffy was one of three senators suspended without pay in November over allegedly improperly claimed housing and travel expenses.

"After consulting my legal team; I have concluded that it would be inappropriate for me to comment while these matters are under study by the RCMP," Duffy said in a statement.

He and suspended senator Pamela Wallin are still under RCMP investigation, but no charges have been laid against them.

Suspended senator Patrick Brazeau and Mac Harb, who resigned from the Red Chamber last summer, are facing charges of fraud and breach of trust.

Both are accused of defrauding the Senate of more than $5,000 by making false or misleading claims for living expenses.

Both have denied any wrongdoing.